Apparatus for removing the ribs from tobacco leaves or the like material and classifying same



March 2 1967 J. GRINZINGER 4 3,310,059

APPARATUS FOR REMOVING THE RIBS FROM TOBACCO LEAVES OR THE LIKE MATERIAL AND CLASSIFYING SAME Filed Sept. 28, 1964 2 Sheets-Sheet 1 J!) van far: J. Gmlvzuvaflz March 21, 1967 J. GRINZINGER 3,316,059

APPARATUS FOR REMOVING THE RIBS FROM TOBACCO LEAVES OR THE LIKE MATERIAL AND CLASSIFYING SAME Filed Sept. 28, 1964 2 Sheets-Sheet 2 .70 van for: J GEM/.2 INGER United States Patent ice 3,310,059 APPARATUS FDR REMOVING THE RIBS FROM TQBACCO LEAVES 0R THE LIKE MATERIAL AND CLASllFYliNG SAME Josef Grinzinger, Lahr, Black Forest, Germany, assignor to Maschinenfahriir llfitl Eisengiesserei A. Heinen G.m.b.H., Varel, Oldenburg, Germany Filed ept. 28, 1964-, er. No. 399,733 Claims priority, application Germany, ept. 30, 1963, B 73,698 Claims. (Cl. 131-146) This invention relates to apparatus for removing the ribs from tobacco leaves and separating by air classification the deribbed parts of the leaves from the mixture formed by such parts and the ribs.

Various designs of this type of apparatus are known. As a rule, such apparatus comprise one or more drums fitted with beating teeth of different shapes and-since they operate On the principle of a disintegratorsurrounded by beater baskets rotatable relative thereto. Relative to the feeding direction of the leaves these drums rotate either with forward or reverse motion and their speed can be adapted to any individual case.

The mixture produced by the deribbing process and consisting of the deribbed leaf parts and of the ribs separated therefrom will be fed by belt conveyors or pneumatically to an air separator arranged in series therewith. By this air separator, the deribbed leaf parts will be separated from the ribs and the oversized material composed of ribs and not yet sufficiently comminuted leaves or ribs, respectively, which are still adhered to by leaf parts will be recirculated into the deribbing device and further disintegrated during the following repeated treatment.

Deribbing is to be effected so that there remains as small as possible an amount of tobacco fines and dust which can hardly be utilized later on. This requirement is not met or at least not in a fully satisfactory manner, by the known apparatus.

The present invention provides an apparatus for deribbing tobacco leaves and subsequently treating the mixture of deribbed leaf parts and ribs and stems, which operates according to the initially specified principle and by which, on the one hand, the quota of fines produced is reduced and, on the other hand and in conjunction therewith, also the efficiency of the air separation is improved at the same time by providing that a substantial part of leaf components that should be fed to further treatment immediately subsequent to air separation is reintroduced in the circuit.

These advantages which result in a considerable increase in efiiciency due to the reduction of the amount of unusable tobacco fines and dust, are achieved according to the invention by a novel design of the leaf disintegrating device, which selectively acts on the ribs or stems and on the deribbed parts of the tobacco leaves, and of the series-connected air separator which in a manner known per se, is pneumatically fed with the mixture of disintegrating deribbed leaf parts and ribs or stems.

For this purpose, the invention proposes to subdivide the deribbing device, which is provided with an impeller fitted with beating teeth, into two seriesconnected, differently-working sections, viz. a first section in which the tobacco leaves are merely subjected to a separating action and a following section in which the tobacco leaves are subjected in the hitherto customary manner to a beating action, the leaf parts completely separated from the ribs and stems in the first section being directly fed from this latter to an air separator so that only the ribs and stems with the leaf parts still adhering thereto are subjected to the subsequent beating treatment and the material resulting from this latter treatment is handled separately by a special air separator. The greater part of the derib- Patented Mar. 21, 1967 bed leaf parts is thus Withdrawn from the beating treatment and in this way prevented from being undesirably disintegrated.

The two mentioned sections are defined by a casing, in which the beating tools rotate, and separated from each other by a connection to the first air separator. In a preferred embodiment of the invention, the first section of the machine, which in the following will be referred to as the separating section, may have for separating tools a hight-adjustable and, if desired, completely removable comb bridge suspended in the interior of the casing in the upper regions thereof immediately adjacent the feed point, which comb bridge has fastened to its inside, a plurality of rows of stationary comb-s constituting the separating tools proper.

in a further embodiment, the rows of combs may be replaced by rotatable separating discs having the function of keeping the separating edges free from deposits, particularly in the case of heavily moistened tobaccoes. The rotating separating discs, moreover, oppose the centrifugal force acting on the tobacco leaves and thus assist the separation. The second section of the machine, which hereinafter will be referred to as the beating section, follows the first or separating section in circumferential direction and extends close up to the feed point. This beating section, which now contains only material consisting for the greater part of ribs, is surrounded by the bar shell forming the beater basket and connected to a second air separator.

This stagewise disintegrating treatment, including a first or careful stage and a second or intensified stage, and the direct separation of the pure leaf parts stripped off in the first stage results in an extraordinary reduction of the amount of fines, which need not be explained further, and, moreover, in a substantially improved separating action in the beating section since there the action of the beating tools is no longer impaired by the presence of a large part of pure leaf material.

In accordance with a special feature of the present invention, the feeding of the tobacco leaves to be treated into the disintegrating device or into the separating section of same is effected so that the tobacco leaves enters as far as possible the interior of the impeller and, sliding outwardly on the beating teeth under the action of centrifugal force, are subjected to the action of the rows of combs or separating discs of the comb bridge which begins immediately above the feed opening for the tobacco leaves, to be stripped off the ribs by the comb rows or separating discs.

The two air separators, one of which is fed with the separated leaf material while the other one is fed with the heavily-rib-containing material from the beating section, may be of any desired design. In accordance with another feature of the present invention, the air separators are conveniently so constructed that they effect stepwise preliminary and after-classification. The air separators, which are preferably used by the invention, consist of two turbulence chambers arranged in tandem in symmetrically superimposed staggered relation. The first air separator is mounted above the deribbing machine on a connection pipe fastened thereto and the wall of this pipe ascends at an inclination and is so curved that the material to be classified is retarded during its upward travel along this wall and thus starts to revolve when entering the separating chamber, which motion is particularly advantageous for the classification under the action of the air flowing through this chamber.

This design results in a double effect due, on the one hand, to the different retardations to which the leaf parts are subjected in dependence on their size and, on the other hand, to their form drag in the air current, the afterclassification being effected at reduced air and particle speeds in the second turbulence chamber arranged above and in series with the first one and generally having the same shape.

The oversized material from the first air separator falls through appropriately shaped guide threads into a bucket wheel sluice closing the classifying or separating chamber at the bottom and from the bucket wheel sluice into the beating section of the disintegrating device arranged therebelow.

The air separator for handling the material treated in the beating section is on principle of the same design and connected through a pipe to the casing in a place below the bar shell of the beating section. The oversized material from this air separator is discharged through a bucket wheel sluice and either fed for after-treatment to a further air separator or, in accordance with another embodiment of the invention, to an after-deribbing device of a known type associated with a further air separator connected in series therewith, for repeated treatment.

Two preferred embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic vertical section through an apparatus according to the invention, all details not necessary for the understanding of the invention having been omitted;

FIG. 2 is a similar view showing another embodiment of the rib removing means; and

FIG. 3 is a top plan view of the rib removing means of FIG. 2.

With reference now to the drawings and more spe cifically to FIG. 1, the numeral 1 generally designates a rib-removing machine. This machine includes a casing in which a beater basket 4 of arcuate cross section is accommodated and an impeller 3 carrying beating teeth is arranged to rotate at preferably variable speed in the direction of feeding the material to be treated. The circumferential region covered by the impeller 3 carrying the beating teeth is subdivided into a separating section designated by A which extends directly behind the feeding station in the direction of travel of the impeller, and a beating section designated by B which is formed by the beater basket 4 and extends as far as the feeding station. Between these two sections there are provided a connection pipe 5 leading to an air separator 2 and a return pipe 6 coming from the air separator 2 and opening into the machine shortly before the beating section B.

The working tool of the separating section A consists according to the embodiment shown in FIG. 1 of an adjustable and completely removable comb bridge 16 which is carried by suspension devices 11 and 12. Arrows indicated in the suspension devices in FIG. 1 show the possibilities of adjusting the comb bridge it Feeding of the tobacco leaves to be treated into the device is effected by means of a conveyor 7 of any desired suitable construction in the direction indicated by the arrow shown in FIG. 1. The impeller 3 arranged to rotate in the direction of feeding the material has spokes 8 carrying the beating teeth 9 and extending somewhat eccentrically with respect to the impeller axis.

As visible, the tobacco leaves drop far into the interior of the impeller 3 "before they are flung outwardly by the action of centrifugal force and are first retained on the beating teeth of the impeller due to the peripheral speed of the beating teeth while passing through the rows of the combs or separating discs 34 (FIGS. 2 and 3) of the comb bridge which strip leaf parts off the stems and ribs of the leaves.

The deribbed leaf parts are passed under the action of a suction air stream through the connection pipe 5 into the air separator 2. The air separator 2 consists according to the preferred embodiment shown in FIG. 1 of two turbulence chambers 14 and 15 arranged in tandem in superimposed staggered relation.

Arrows shown in FIG. 1 indicate the direction of movement of the material passing through these two turbulence chambers having the function already explained above. After separation, the fine deribbed leaf parts are drawn off through a pipe 21 and a conventional tobacco sluice whereas the oversized material is again introduced into the machine through a bucket-wheel sluice 16 and the return pipe 6 at a point situated in front of the beating section B in the direction of travel of the impeller 3.

As shown in FIG. 1, the connection pipe 5 has such a curvature that the stripped-off material is directed in the direction of arrows shown in FIG. 1 along an obliquelyupwardly-extending wall 13 of the first turbulence chamber 14 and a curved wall 22'} following thereto and is decelerated thereby so that a turbulent motion is imparted to the material which is particularly advantageous for subjeCting the material to a classifying action. Flaps 17 and 18 serve for air regulation.

The numerals 19 and 22 designate drive means or driving motors for the bucket-wheel sluice 16 and the impeller 3, respectively, which may be variable if desiredc The material further treated in the beating section B passes through a hopper 23 and a suction pipe 24 into a second air separator 25 which is fundamentally of the same construction as the first air separator 2, i.e. has two turbulence chambers 26 and 27 arranged in tandem. The leaf parts separated in this second air separator 25 are drawn off from the upper region of the air separator through a pipe The oversized material is discharged through a bucket-wheel sluice 2? and subjected to a repeated treatment in a mechanism 39 for the ultimate removal of ribs, which is connected through a channel 31 to a further air separator 32. having a discharge sluice 33 for the oversized material consisting of ribs and stems entirely freed of fine leaf parts.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

I claim:

1. An apparatus for removing ribs from tobacco leaves and classifying by air separation the leaf parts separated from ribs and stems, comprising a rib-removing machine including an impeller fitted with heating teeth and a beater basket cooperating with said impeller, said rib-removing machine having a separating section and a beating section following said separating section and formed by said heater basket, a first air separator connected to said ribremoving machine between said separating section and said heating section and receiving the deribbed leaf parts stripped-off in the separating section of the rib-removing machine, and a second air separator connected to the beating section of the rib-removing machine, the oversized leaf parts remaining over after separation being reintroduced at least from said first air separator in the region between the separating section and the beating section into the rib-removing machine.

2. Apparatus as claimed in claim 1, wherein the separating section of the rib-removing machine includes separating tools comprising an adjustable comb bridge which directly follows the point where the leaves are fed into the apparatus and to which the leaves can be raised by the impeller rotatable in the direction of feeding the leaves, spokes being provided on the impeller and carrying the beating teeth.

3. An apparatus as claimed in claim 2, wherein rows of combs are provided on the comb bridge.

4. An apparatus as claimed in claim 2, wherein rotatable separating discs are provided on the comb bridge, which can clean themselves on the comb bridge due to their rotation and counteract the centrifugal force as Well as clear between the beating teeth on the impeller.

5. An apparatus as claimed in claim 2, wherein the spokes of the impeller are each angled forwardly in the direction of impeller rotation relative to a radius thereof and mounted on the impeller in such a manner that the leaves fed into the apparatus can drop far into the interior of the impeller and can be raised up to the comb bridge while retained on the beating teeth.

6. An apparatus as claimed in claim 5, wherein a connection pipe connects the separating section with the first air separator and at least the first air separator comprises two turbulence chambers arranged in symmetrically superimposed staggered relation and connected to the connection pipe.

7. An apparatus as claimed in claim 6, wherein the walls of a passage formed in the connection pipe and serving for directing the material from the separating section into the first air separator, are so curved that the material is decelerated while changing its direction of movement and is imparted a turbulent motion.

8. An apparatus as claimed in claim 7, wherein a second rib-removing machine is connected to the second air separator and the oversized material remaining over after separation in the second air separator is also introduced 6 into the following second rib-removing machine in the region situated in front of the beating sector.

9. An apparatus as claimed in claim 8, wherein the second rib-removing machine comprises a mechanism for the ultimate removal of ribs and a third air separator is connected to the second rib-removing machine.

10. An apparatus as claimed in claim 9, wherein the third air separator is of the same construction as the first air separator.

References Cited by the Examiner UNITED STATES PATENTS 96,257 10/1869 Muller 131-145 2,150,493 3/1939 Dahlstrom et a1. 131145 2,667,174 1/1954 Eissmann l31146 3,200,947 8/1965 Wochnowski 131-146 X 3,245,415 4/1966 Koch et al. l31146 FOREIGN PATENTS 864,367 4/ 1961 Great Britain.

SAMUEL KOREN, Primary Examiner.

H. P. DEELEY, JR., Assistant Examiner. 

1. AN APPARATUS FOR REMOVING RIBS FROM TOBACCO LEAVES AND CLASSIFYING BY AIR SEPARATION THE LEAF PARTS SEPARATED FROM RIBS AND STEMS, COMPRISING A RIB-REMOVING MACHINE INCLUDING AN IMPELLER FITTED WITH BEATING TEETH AND A BEATER BASKET COOPERATING WITH SAID IMPELLER, SAID RIBS-REMOVING MACHINE HAVING A SEPARATING SECTION AND A BEATING SECTION FOLLOWING SAID SEPARATING SECTION AND FORMED BY SAID BEATER BASKET, A FIRST AIR SEPARATOR CONNECTED TO SAID RIBREMOVING MACHINE BETWEEN SAID SEPARATING SECTION AND SAID BEATING SECTION AND RECEIVING THE DERIBBED LEAF PARTS STRIPPED-OFF IN THE SEPARATING SECTION OF THE RIB-REMOVING MACHINE, AND A SECOND AIR SEPARATOR CONNECTED TO THE BEATING SECTION OF THE RIB-REMOVING MACHINE, THE OVERSIZED LEAF PARTS REMAINING OVER AFTER SEPARATION BEING REINTRODUCED AT LEAST FROM SAID FIRST AIR SEPARATOR IN THE REGION BETWEEN THE SEPARATING SECTION AND THE BEATING SECTION INTO THE RIB-REMOVING MACHINE. 